Apparatus for detecting position and format of a film cassette

Abstract

An apparatus configured for an insertion of a cassette comprises at least one distance sensor operably measuring in a contactless manner a distance from a corresponding location on the apparatus to the inserted cassette. An electronic evaluator is operably connected to the at least one distance sensor to receive at least one distance signal corresponding to distances measured by at least one distance sensor, such that the electronic evaluator generates a position signal, resulting from the at least one distance signal, which is dependent on a dimension and a position of the inserted cassette in the apparatus. A control unit is operably connected to the electronic evaluator such that the control unit receives the position signal from the electronic evaluator.

1. An apparatus configured for an insertion of a film cassette, the apparatus comprising a fixture operable to retain the film cassette in a position within the apparatus where the position is (1) completely variable and unencumbered by any mechanical guides in terms of one direction in space with respect to a first and a second wall of the apparatus and (2) fixed in terms of a second direction;
 a first distance sensor that measures a first distance “d” from a first wall of the apparatus to a first side of the inserted film cassette in a contactless manner; 
 a second distance sensor that measures a second distance “e” from a second wall of the apparatus to a second side of the inserted film cassette in a contactless manner; and 
 a processor that derives a format of the inserted film cassette and/or a position of the inserted film cassette within the apparatus as a function of the contactlessly measured first distance d and second distance e. 
 
   
   
     2. The apparatus of  claim 1  wherein the apparatus is mountable in a catapult frame drawer for an x-ray system. 
   
   
     3. The apparatus of  claim 1  wherein the apparatus comprises a catapult frame drawer for an x-ray system. 
   
   
     4. The apparatus of  claim 1 , wherein the film cassette is an x-ray imaging film cassette. 
   
   
     5. The apparatus of  claim 1 , wherein the second distance sensor is disposed in a location on the apparatus opposite the first distance sensor, such that the second distance e is measured in contactless manner in a direction opposite the first distance d. 
   
   
     6. The apparatus of  claim 1 , wherein a third distance sensor is disposed on the apparatus such that a third distance “b” from the third distance sensor to the inserted film cassette in a direction perpendicular to the one direction in space is measured in contactless manner. 
   
   
     7. The apparatus of  claim 1 , wherein the second distance sensor is disposed in a location on the apparatus such that the second distance e from the second distance sensor to the inserted film cassette in a direction perpendicular to the one direction in space is measured in contactless manner. 
   
   
     8. The apparatus of  claim 1 , further comprising an electronic evaluator operably connected to at least one of the first and second distance sensors to receive at least one distance signal corresponding to a distances measured by at least one of the first and second distance sensors, such that the electronic evaluator generates a position signal, resulting from the at least one distance signal, which is dependent on a dimension and a position of the inserted film cassette in the apparatus. 
   
   
     9. The apparatus of  claim 1 , wherein the processor is operable to derive a cassette width from the distances d and e, measured in a traverse direction to a longitudinal length of the apparatus, and from a width “c” of the apparatus in the traverse direction as follows:
   cassette width=( c/ 2− d )+( c/ 2− e ). 
 
   
   
     10. The apparatus of  claim 1 , wherein the processor is operable to derive a displacement of a center of the inserted film cassette in the traverse direction to the longitudinal length of the apparatus that is derived as follows:
   displacement of cassette center=( d−e )/2. 
 
   
   
     11. The apparatus of  claim 1 , wherein when a third distance sensor measures a distance “b” to a third side the inserted film cassette, and a distance between the third distance sensor and the center of the inserted film cassette is equal to “a”, then the processor is operable to derive a dimension of the inserted film cassette in the longitudinal direction of the apparatus that is derived as follows:
   longitudinal cassette dimension=( a−b )*2. 
 
   
   
     12. An x-ray system comprises an apparatus configured for an insertion of a cassette, the apparatus comprising:
 a fixture operable to retain the cassette in a position within the apparatus where the position is free of any mechanical guides in terms of a direction in space with respect to a wall of the apparatus such that the position is completely variable an entire distance from at least one of an end or a side face of the inserted cassette to the wall; 
 a first and a second distance sensor each respectively operably measuring in a contactless manner a distance from a predetermined location on the apparatus to the inserted cassette, the first distance sensor contactlessly measures a distance “d” to a first side of the inserted cassette and the second distance sensor contactlessly measures a distance “e” to a second side of the inserted cassette; and 
 a processor that derives a displacement of the inserted cassette relative to a center of the apparatus as a function of the contactlessly measured distances d and e. 
 
   
   
     13. The x-ray system of  claim 12  further comprising a control unit, wherein the control unit directs the taking of x-rays based upon a format signal, the format signal being dependent upon cassette dimensions of the inserted cassette determined using the signals received from the first and second distance sensors. 
   
   
     14. The x-ray system of  claim 12 , wherein the apparatus comprises a catapult frame drawer for an x-ray system and the processor is operable to derive a cassette width from the distances d and e, measured in a traverse direction to a longitudinal length of the apparatus, and from a width “c” of the apparatus in the traverse direction as follows:
   cassette width=( c/ 2− d )+( c/ 2− e ). 
 
   
   
     15. A method of inserting a cassette, comprising:
 inserting the cassette into an apparatus to a variable position that is (1) fixed in a first direction within the apparatus and (2) unencumbered by any guides in a second direction such that the cassette is freely positionable in the second direction an entire distance from a face of the cassette to the wall; 
 contactlessly determining (1) a first distance “d” from a first wall of the apparatus to a first side of the cassette and (2) a second distance “e” from a second wall of the apparatus to a second side of the cassette after the cassette has been inserted into the apparatus; and 
 determining the position of the cassette enclosed within the apparatus as a function of the contactlessly determined first distance d and second distance e. 
 
   
   
     16. The method of  claim 15 , comprising determining the format of the cassette enclosed within the apparatus as a function of the contactlessly determined first distance d and second distance e, and information stored in a memory unit. 
   
   
     17. The method of  claim 15 , comprising correctly positioning the cassette within the apparatus when it is determined that the cassette is incorrectly positioned within the apparatus, wherein the apparatus is an x-ray system such that correctly positioning of the cassette alleviates needless radiation exposure to a patient. 
   
   
     18. The method of  claim 15 , wherein the apparatus comprises a catapult frame drawer for an x-ray system and is operable to indicate correct positioning of the film cassette despite the catapult frame drawer being closed.